A Novel Nuclear Import Pathway for the Transcription Factor TFIIS

Author:

Albertini Markus1,Pemberton Lucy F.1,Rosenblum Jonathan S.1,Blobel Günter1

Affiliation:

1. Laboratory of Cell Biology, Howard Hughes Medical Institute, The Rockefeller University, New York, New York 10021

Abstract

We have identified a novel pathway for protein import into the nucleus. We have shown that the previously identified but uncharacterized yeast protein Nmd5p functions as a karyopherin. It was therefore designated Kap119p (karyopherin with Mr of 119 kD). We localized Kap119p to both the nucleus and the cytoplasm. We identified the transcription elongation factor TFIIS as its major cognate import substrate. The cytoplasmic Kap119p exists as an approximately stoichiometric complex with TFIIS. RanGTP, not RanGDP, dissociated the isolated Kap119p/TFIIS complex and bound to Kap119p. Kap119p also bound directly to a number of peptide repeat containing nucleoporins in overlay assays. In wild-type cells, TFIIS was primarily localized to the nucleus. In a strain where KAP119 has been deleted, TFIIS was mislocalized to the cytoplasm indicating that TFIIS is imported into the nucleus by Kap119p. The transport of various substrates that use other karyopherin-mediated import or export pathways was not affected in a kap119Δ strain. Hence Kap119p is a novel karyopherin that is responsible for the import of the transcription elongation factor TFIIS.

Publisher

Rockefeller University Press

Subject

Cell Biology

同舟云学术

1.学者识别学者识别

2.学术分析学术分析

3.人才评估人才评估

"同舟云学术"是以全球学者为主线,采集、加工和组织学术论文而形成的新型学术文献查询和分析系统,可以对全球学者进行文献检索和人才价值评估。用户可以通过关注某些学科领域的顶尖人物而持续追踪该领域的学科进展和研究前沿。经过近期的数据扩容,当前同舟云学术共收录了国内外主流学术期刊6万余种,收集的期刊论文及会议论文总量共计约1.5亿篇,并以每天添加12000余篇中外论文的速度递增。我们也可以为用户提供个性化、定制化的学者数据。欢迎来电咨询!咨询电话:010-8811{复制后删除}0370

www.globalauthorid.com

TOP

Copyright © 2019-2024 北京同舟云网络信息技术有限公司
京公网安备11010802033243号  京ICP备18003416号-3